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PH1123 Microbiology > Mock exam > Flashcards

Mock exam Flashcards

1
Q

what are the organelles surrounded by a lipid membrane

A
  • nucleus
  • endoplasmic reticulum
  • golgi apparatus
  • mitochondria
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2
Q

what is the difference between cytosol and cytoplasm?

A

cytosol: fluid contained within the cytoplasm
cytoplasm: entire content within the cell membrane except the nucleus

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3
Q

elaborate on the asymmetry of the plasma membrane

A
  • composition of membrane leaflets is highly uneven
  • maintained by flippases and floppases
  • extracellular leaflet: phosphatidylcholine, SM, phosphatidylserine, phosphatidylethanolamine
  • CHL resides in cytoplasmic leaflet
  • asymmetry creates a difference in orientation and positioning of proteins
  • difference in lipids/protein/carb composition
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4
Q

what types of lipids and proteins are found in plasma membrane?

A

lipids: glycolipids/cholesterol/phospholipids
proteins: intrinsic (integral) /extrinsic (peripheral)

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5
Q

classify plasma membrane proteins based on their function

A
  • structural proteins
  • enzymes
  • transport proteins
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6
Q

what is endocytosis and what are the different endocytic pathways?

A

endocytosis: process by which cells take in substances from outside of the cell by engulfing them in a vesicle

endocytic pathways

  1. pinocytosis
  2. receptor mediated endocytosis
  3. phagocytosis
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7
Q

what’s the difference between each endocytic pathway?

A

phagocytosis: engulfment of large particles that pinch off from the membrane to form a vacuole that surrouds the particle

receptor mediated endocytosis: ligands bind to cell surface receptors on membrane

pinocytosis: small vesicles dissolve small material in liquid

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8
Q

what are the general steps of phagocytosis?

A
  1. engulfment
  2. phagosome formation
  3. phagolysosome digestion
  4. expulsion of undigested material
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9
Q

what cells are capable of phagocytosis?

A
  • neutrophils
  • monocytes
  • dendritic cells
  • macrophages
  • mast cells
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10
Q

what enzymes are found in lysosomes?

A

hydrolytic enzymes

e.g. proteases, nucleases, glycosidases, lipases, phospholipases, phosphatases, sulfatases

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11
Q

what is the role of iron in cells?

A
  • electron transport chain of the mitochondria depends on iron as an electron acceptor/donor
  • many enzymes of electron transport chain are iron dependent (cytochrome c/cytochrome oxidase/succinate dehydrogenase)
  • it helps oxygenate blood cells and haemoglobin by binding oxygen thus aiding oxygen transport to tissues
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12
Q

what genes are critical for cancer?

A

oncogenes

tumor suppressor genes

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13
Q

what are apolipoproteins and what do they do?

A

proteins that bind lipids to form lipoproteins

they transport lipids in blood, CSF, and lymph

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14
Q

what diseases are caused by apolipoproteins?

A
  • alzeheimer → amyloid beta peptide (APO E)
  • parkinson’s → alpha synuclein (APO D)
  • spongiform encephalopathies → prion proteins (APO E)
  • familial amyloiditic polyneuropathy → transthyretin (APO A)
  • huntington’s → polyQ
  • familial amyotrophic lateral sclerosis → superoxide dismutase 1
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15
Q

define autophagy

A

destruction of damaged cellular components occuring in vacuoles within the cell

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16
Q

what is the role of the cytoskeleton in membrane traffic?

A

provides support and directionality

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17
Q

compare and contrast:

prokaryotes and eukaryotes

A
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18
Q

compare and contrast:

gram negative and gram positive bacteria

A
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19
Q

what are the different bacterial structures and what are their functions?

A
  • pili → genetic exchange (conjugation)
  • fimbrae → adhesins (attachment)/biofilm formation/hemagglutination
  • flagella → motor movement/flagellin protein
  • S-layer → increase robust/permeability barrier
  • capsule/slime → barrier against antibacterials/dessication-phagocyte protection
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20
Q

what is the extracellular polysaccharide in

(1) pseudomonas aueriginosa
(2) leuconostoc mesateronides

A
  1. alginate
  2. dextran
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21
Q

what is the function of dextran

A

provides protection against external environment

enhances adhesion to solid surfaces

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22
Q

how do bacteria divide and grow?

A

most bacteria reproduce by binary fission

bacterial growth: change in population rather than size or mass

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23
Q

what is binary fission?

A

division into two identical daughter cells

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24
Q

what are the growth requirements for bacteria?

A
  • warmth
  • moist (water)
  • proteins
  • neutral or slightly acidic pH
  • oxygen
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25
Q

what is microbial enumeration test?

A

quantative test that determines the total aerobic microbial count and total yeast and mold count present in test product

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26
Q

what are the methods available for microorganism enumeration?

A
  • direct
  • indirect
  • viable
  • total cell count
  • RMM:
    • growth based
    • direct measurement
    • cell component analysis
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27
Q

what bacterial classes are there

A
  1. spherical (cocci)
  2. rod (bacilli)
  3. spiral (spirilla)
  4. coma (vibrois)
  5. corkscrew (spirochaetes)
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28
Q

why is bacterial identification important

A

because it is essential for correct diagnosis and treatment and trace back of disease outbreaks

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29
Q

what are some traditional and modern identification methods?

A

traditionals:

  • cultivation (growth requirement)
  • cultivation (selective agar)
  • biochemical profiling

New/rapid:

  • serological testing
  • nucleic acid techniques
  • MALDI TOF
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30
Q

draw a bacterial spore structure

A
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31
Q

how do sporulation and germination occur?

A

Spore is metabolically dormant structure produced during unfavorable condition by the process called sporulation. Sporulation occur during late log phase or early stationary phase. Under favorable condition spores germinate to give vegetative cell.

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32
Q

why are spores resistant to antimicrobials?

A

because they are highly dehydrated with no metabolic activity and their constituents of small acid soluble proteins dipicolinic acid and their multilayered structure

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33
Q

true or false

most spore forming bacteria are gram positive

A

true

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34
Q

define sterilization

A

process that kills all microorganisms including spores

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35
Q

which antibiotics are most likely to cause c.diff?

A

broad spectrum antibiotics like: cephalosporins/fluoroquinolones/ampicillin/amoxicillin/clindamycin

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36
Q

explain the cell cycle of chlamydia

A
  • they alternate between infectious extracellular elementary body and reticulate body
  • elementary bodies enter mucosal cells and differentiate to reticulate bodies in membrane bound compartment
  • replication occurs, reticulate bodies redifferentiate into elementary bodies and released from host cell to infect other cells
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37
Q

what are the features of mycobacteria?

A
  • hydrophobic cell wall, peptidoglycan linked to arabinogalactan esterfied to mycolic acid
  • lipids 25% of dry weight
  • mycolic acid, high molecular weight (3 hydroxy fatty acid)
  • cord factor, parallel alignment of rows of bacilli
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38
Q

what treatments are available for TB

A
  • isoniazid
  • rifampicin
  • pyrazinamide
  • ethambutol
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39
Q

what are the common routes of infection?

A
  • direct contact
  • fomites
  • aerosols
  • oral
  • vector borne
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40
Q

what is the normal flora?

A

microbes that are both helpful and potentially harmful occupying the a habitat (human)

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41
Q

what is a virulence factor?

A

microbial product that contributes to virulence

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42
Q

what is virulence?

A

intensity of pathogenicity of an organism

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43
Q

what are toxins?

A

substance of organisms that damage the host

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44
Q

what is an opportunistic pathogen?

A

organism that becomes pathogenic following a perturbation to a host / disruption of microflora

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45
Q

what is the difference between endotoxin and exotoxins?

A

endotoxins are toxic at high doses whereas exotoxins are can be extremely toxic at low doses.

endotoxins are released when bacterial cell dies

exotoxins produced during growth/division

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46
Q

what exotoxins are there?

A

neurotoxins

enterotoxins

cytotoxins

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47
Q

what is the toxic molecule of gram negative?

A

lipopolysaccharide molecule (Lipid A)

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48
Q

what’s the difference between DNA and RNA

A
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49
Q

what’s the difference between DNA polymerase and RNA polymerase

A
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50
Q

what factors affect antimicrobial treatment?

A
  • bacterial status (resistance/biofilm/susceptibility)
  • antimicrobial concentration and subinhibitory concentration
  • host factors (serum effect/gut impact)
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51
Q

what are mycoses?

A

infections caused by fungus invading tissues and causing, superficial/subcutaneuous/systemic infections

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52
Q

where is candida present in the normal flora?

A

mouth

skin

intestine

53
Q

draw the structure of a yeast cell

A
54
Q

draw a yeast/fungi cell wall

A
55
Q

how do yeast cells reproduce?

A

budding, whereby mother cell grows a protrusion (bud) until it’s the same size as the mother cell and splits from it

56
Q

what antifungal drugs are there?

A

polyene: nyastatin + amphoterecin B
azole: itraconazole + ketoconazole
echinocandins: caspofungin/micafungin/anudiulafungin
synthetic: flucytosine

57
Q

what are dermatomycoses?

A

fungal skin, hair, or nail infections by dermatophytes (ringworm)

58
Q

what is aspergillosis?

A

fungal infection caused by aspergillus a common mold that lives both indoors and outdoors

59
Q

describe the structure if mold and draw it

A

long branched thread-like filaments of hyphae that form mycelium

60
Q

explain how mold reproduces sexually and asexually

A

molds reproduce sexually when they are starved, in which 4 haploid cells fuse into two and further into one (increase genetic diversity/survival)

they reproduce asexually when there’s plentiful food supply, producing 2 identical daughter diploid cells

61
Q

give examples of viruses that use the following transmission means

direct contact

airborne

food/water

arthropod

A

direct contact → aids/hiv/hsv/hpv/leukemia/hepatitis b/c

airborne → chickenpox/influenza/measles/mumps/rubella/corona

food/water → gastroenteritis/norovirus/hepatitis A/poliomyelitis

arthropod → yellow fever

62
Q

describe the basic structure of viruses

A

nucleic acid covered by capsid forming the nucleocapsid, with an envelope covering it along with viral receptors

63
Q

what are the general steps of viral replication?

A
  1. attachment and penetration
  2. macromolecular synthesis
  3. assembly of progeny virions and release from host cell
64
Q

describe structure of influenza

A

spherical with an outer lipid membrane (envelope) derived from host cell

65
Q

what are the spike like protrusions on influenza virus

A

hemagglutinin (HA) and neuraminidase (NA)

66
Q

what is the difference in antigenic drift and antigenic shift?

A

antigenic drift: two virus strains infect the same cell and mix during assembly of new viruses e.g. h3n2+h5n1=h5n2

antigenic drift: small changes in the virus over a period of time, producing new strains not recognized by immune system and are difficult to treat/vaccinate

67
Q

how does influenza replicate inside host cell

A

influenza is a single stranded negative sense RNA virus, they have genomes which consist of more than 1 RNA viruses, transcription results in unique mRNA for each protein rather than a single polycistemic mRNA

68
Q

define reassortment

A

process by which influenza viruses swap gene segments

69
Q

how do herpes viruses replicate

A

herpes viruses are DNA containing viruses, which means they make mRNA using strategies similar to host cell replication, in which DNA is transcribed into mRNA in the host cell nucleus with host cell enzymes resulting in early and late transcripts that encode for structural proteins and those required for replication

70
Q

what is herpes latent and productive infection?

A

productive infection: Following primary infection, the virus replicates productively within mucosal epithelial cells and enters sensory neurones via nerve termini

latent infection: e virus is then transported to neuronal cell bodies where latency can be established (it can reactivate and generate new virus progeny when transported back to periphery)

71
Q

explain how herpes viruses reactivate

A
  • initiation of viral lytic gene expression
  • newly formed capsids are transported to axonal termini
  • infectious virus released from axon and infects epithelial cell resulting in recurrent infection and virus shedding
72
Q

what type of viruses are corona viruses

A

single stranded positive sense RNA

73
Q

what enzymes does corona use in replication

A

RNA dependent RNA polymerase

74
Q

what causes RNA-RNA recombination in corona

A

high intrinsic error rate, introducing multiple nucleotide changes, jump across templates

75
Q

what mediates RNA proofreading

A

viral RNA exonuclease

76
Q

what accounts for the highly diverse populations in viruses like corona?

A

the combination of RNA recombination due to high polymerase error and regulated replication fidelity favors the generation of recombinant and highly diverse viruses

77
Q

how is SARS-COV-2 transmitted?

A

close contact

78
Q

what is viral shedding?

A

release of virus progeny after assembly in host cell

79
Q

what is SARS and what are the subtypes?

A

it stands for severe acute respiratory syndrome (SARS) that is a viral respiratory disease caused by coronaviruses

80
Q

what type of virus is corona?

A

enveloped, positive sense RNA virus

81
Q

how do antivirals affect viral processes in HIV?

A

zidovudine, is a reverse transcriptase inhibitors, It inhibits the activity of HIV-1 reverse transcriptase (RT) via DNA chain termination after incorporation of the nucleotide analogue. It competes with the natural substrate dGTP and incorporates itself into viral DNA.

82
Q

how does HIV replicate?

A

uses CD4+ cells to replicate, The retroviruses, such as HIV, contain single-stranded positive-sense RNA but employ a unique replicative strategy using a DNA intermediate. Viral positive-sense RNA serves as a template for a virion-associated RNA-dependent DNA polymerase (reverse transcriptase). The DNA is then integrated into host chromosomal DNA, where it resides for the life of the cell. Transcription of the integrated viral DNA, like transcription of host cell genes, is carried out by host cell DNA-dependent RNA polymerases

83
Q

what is HIV and AIDS?

A

HIV is a retrovirus that primarily infects CD4+ cells, macrophages, and dendritic cells

aids: acquired immunodeficiency syndrome that describes life threatening infections occurring due to damaged immune system caused by HIV

84
Q

what is the CD4+ count of AIDS

A

below 200 cells per microlitre

85
Q

viruses are mainly diagnosed by symptoms and clinical manifestations, what tests can be done to confirm diagnosis?

A

direct/indirect: isolation (immunofluoroescence)/ antigens/antibodies/PCR

biological specimens: nasopharynx swab/throat swab/rectal swab/eye swab/ lesion swab

86
Q

what is malaria

A

unicellular, eukaryotic, heterotrophic microorganism that are sometimes parasitic depending on the life stage found in aqueous environments and they are transmitted via arthropod vectors

87
Q

define helminths

A

parasitic worms such as flukes and tapeworm

88
Q

what diseases are caused by helminths?

A

schistosomiasis

lymphatic filariasis

cysticercosis

onchocerciases

89
Q

what is the role of microbiome?

A

metabolism → biochemical pathway for non digestible foods (cellulose/gum/hemicellulose/pectins). synthesize vitamins k and b12 and develop caucum

immune development: produce antimicrobials (fatty acids/peroxides) and compete for nutrient sites in sites of attachment in the gut preventing colonization

gut-brain-axis → stress influences microbiota composition and integrity of gut epithelium

90
Q

what diseases result from the disruption of normal microflora?

A

inflammatory bowel syndrome

obesity/diabetes 2

atopic eczema and allergies

91
Q

what are probiotics

A

microorganisms believed to provide health benefits when consumed

92
Q

what are the sources of contamination?

A
  • contaminated manure
  • irrigation water
  • soil
  • livestock/wildlife
93
Q

how can you minimize, control or eliminate contamination?

A

water → chemical treatment NaCl/membrane filtration/UV irradiation 250nm/heating 80c

operator → gloves/good hygiene/cover when sneezing

buildings → good ventilation/disinfectant/filtration/floor cleaning/avoid drainage in manufactures/dusting

packages → maintain integrity (shelf-life)/safe delivery

equipment → sterilizaition/disinfection/disposable (single use)

air → filtration (HEPA)/chemical disinfection/UV radiation

94
Q

what are the benefits of microbes

A
  • transform heavy metals like mercury to non toxic form
  • petroleum biodegradation
  • xenobiotic degradation
95
Q

how have microorganisms been harnessed for various purposes?

A
  • leuconostoc bacteria can produce dextran from sucrose which is an antithrombotic that improves tissue function
  • clostridium botilinum produces botilinum toxin that is used in minute amounts in the cosmetic industry to prevent wrinkles and to treat dystonia
  • bacillus sphaericus produce 51 & 42 kDA which are toxic to larvae and used in waters where larvae develop
96
Q

Describe the stereochemistry of amino acids

A

Almost all amino acids contain a chiral centre on the alpha carbon. All naturally occurring amino acids have L-stereochemistry, i.e. they have the same configuration as the reference compound glyceraldehyde. D-amino acids are very rare, and are the product of biosynthesis

97
Q

Explain what is unusual about the stereochemistry of glycine. Explain your answer

A

Glycine has no chiral centre and therefore cannot exist in L/D-forms. The alpha carbon does not have four non-identical groups attached, two are hydrogen (i.e. identical

98
Q

Explain how i) acidic and ii) basic conditions would affect the amino acids shown

A

Acidic conditions will protonate the basic side chain of Lys, becoming positively charged. Basic conditions will deprotonate the acidic carboxylic acid group, becoming negatively charged. (You could also, or might be asked, to draw the resulting structures

99
Q

Provide a concise definition of a peptide

A

A small protein containing 50 or less amino acid residues

100
Q

Briefly describe the nomenclature of peptides

A

Peptides should be named, using three letter or single letter amino acid abbreviations starting from the N-terminal residue and listing sequentially to the C-terminal. Abbreviations separated by dashes.

101
Q

Consider the decapeptide (below) and answer the following questions: Lys-Ala-Val-Ala-Leu-Ser-Ile-Leu-Val-Asp

a) Name the N-terminal amino acid.
b) Name the C-terminal amino acid.

A

a. Lysine
b. Aspartic acid

102
Q

Lys-Ala-Val-Ala-Leu-Ser-Ile-Leu-Val-Asp

State the side chain property of each amino acid in the peptide

A

Lys – basic

Ala, Val, Leu and Ile – hydrophobic

Ser – polar; Asp – Acidic

103
Q

Lys-Ala-Val-Ala-Leu-Ser-Ile-Leu-Val-Asp

How you would expect this peptide to fold in an aqueous solution? Fully explain your answer and include a rough sketch of this conformation.

A

in an aqueous environment, hydrophobic residues e.g. Ala, Val etc would be folded away from water into the interior of the protein. Hydrophilic residues, e.g. Ser, would face the solvent. Charged side chains would form an interaction where possible.

104
Q

Lys-Ala-Val-Ala-Leu-Ser-Ile-Leu-Val-Asp

Would you predict this peptide to be water soluble? Briefly explain your answer

A

Will have some water solubility, although mostly non-polar amino acids there are three polar aa’s, two of which form a salt. OR – will not be soluble in water as 7 non-polar aa’s versus 3 polar.

105
Q

describe the structure of a globular protein

A

Compact (tightly folded), roughly spherical, structurally complex, comprised of many elements of secondary structure, e.g. alpha helix, beta sheet, often clearly defined active site / cleft, internal bonding to maintain structure, e.g. disulfide bridges

106
Q

give an example of a globular protein

A

trypsin (all enzymes)

107
Q

Describe the general properties of a globular protein.

A

Hydrophobic interior, hydrophilic exterior, water soluble, often function as catalysts

108
Q

Describe how the three-dimensional structure of a globular protein is maintained.

A

ionic interactions, hydrogen bonding, hydrophobic interactions, covalent crosslinks

109
Q

true or false

the alpha helix is a double helix

A

false

The alpha helix is a single peptide backbone coiled around itself and stabilised by intra-strand H-bonds. [By contrast, DNA is an example of a double helix – two chains stabilised by inter-strand H-bonds]

110
Q

true or false

The native conformation is the biologically active form of a protein.

A

true

All proteins fold spontaneously into a conformation that is biological active

111
Q

true or false

The peptide bond usually adopts a trans conformation

A

true

Cis-amide bonds force unfavourable steric interactions between aa side chains and are not commonly found in proteins

112
Q

true or false

parallel beta sheets are more stable than antiparallel beta sheets

A

false

Anti-parallel beta sheets are more stable – the network of inter-strand H-bonds are better aligned and more stable in the anti-parallel type.

113
Q

what is Native conformation

A

Proteins do not exist as a linear conformation of amino acids (the primary sequence) they fold very specifically into a specific conformation called the native conformations. This is generally the biologically active form of the protein

114
Q

what is alpha Helix

A

. Alpha helix important form of secondary protein structure. Single polypeptide strand coiled in a tight helix excluding water from the centre. + + Describe properties and H-bonding network etc. Some proteins composed exclusively of a-helix, usually as coils of coils, e.g. keratin, collagen. Also common in membrane spanning receptors

115
Q

what is a Non-essential amino acid.

A

An amino acid that can be biosynthesized with the body and therefore is not essential in the diet. E.g. Ala, Gly, Pro, Ser etc. It requires energy and raw materials to synthesize aa’s so in practice these are obtained from diet whenever possible

116
Q

what is a Cyclic peptide

A

A polypeptide joined via an amide (peptide) bond between the N and C terminal amino acids creating a continuous cyclic peptide backbone. Have pharmaceutical use. E.g. ciclosporin, a microbial cyclic peptide that contains non-coding biosynthesized amino acids. When non-amino acid groups are incorporated known as a pseudo-peptide

117
Q

Very briefly describe how enzymes function as catalysts

A

…by lowering the activation energy barrier to the reaction. Achieved by precise orientation of the substrate in the active site in a reactive conformation and provide missing functional groups or cofactors for the reaction. Enzymes provide the reaction ‘template’.

118
Q

Briefly describe how enzymes are named and classified. Illustrate your answer with suitable examples

A

Two methods, trivial and systematic. Trivial – name associated with the function or substrate (or both) is suffixed with –ase. E.g. L-dopa decarboxylase or DNA polymerase. Systematic system (enzyme commission: EC) assigns a unique serial number comprised of 4 digits. First digit is one of the six classes (list them) followed by two sets of sub classes and finally the unique identifier, e.g. alcohol dehydrogenase = EC1.1.1.1.

119
Q

Many enzymes require cofactors for their biological function. Discuss this statement using alcohol dehydrogenase and another enzyme of your choice to illustrate your answer.

A

The 20 amino acids that occur naturally in proteins have limited functional groups / chemistry in their side chains. Co-factors, which can be metal ions or organic molecules (co-enzymes) supply this chemistry. Alcohol dehydrogenase uses two co-factors, a zinc ion and a NAD+ coenzyme. The zinc aligns the substrate in the active site to the –OH group. The NAD+ contains a functional group that accepts a proton (i.e. dehydrogenation). Could also include a sketch? Another example could be L-Dopa decarboxylase. The enzyme uses a co-enzyme (pyridoxal phosphate/vitB6) to facilitate the removal of a carboxylic acid. The co-enzyme contains an aldehyde functional group – not found in amino acids – to form an intermediate (imine) with the substrate etc etc

120
Q

Briefly discuss the importance of metals in protein function. Give one example of a protein that requires a metal atom to function

A

Proteins containing metal ions are known as metalloproteins or metalloenzymes if they have a catalytic function. The 20 amino acids that occur naturally in proteins have limited functional groups / chemistry in their side chains. Co-factors, which can be metal ions or organic molecules (co-enzymes) supply this chemistry. Metals are important in transport proteins (e.g. haemoglobin, Fe required to bind, store then release O2, four Fe atoms held in 4 prosthetic haem groups etc etc). Alcohol dehydrogenase and Zn etc etc

121
Q

what are the products of the following:

glycolysis

pyruvate → acetyl coa

krebs cycle

A

glycolysis: 2 pyruvate + 2ATP +2 NADH

pyruvate → acetyl coa: 2 NADH per glucose

krebs: coa to co2+ 2GTP + 6NADH + 2 FADH2

122
Q

define fatty acid

A

occur as esters in natural fats and oils and FFA in blood

123
Q

what’s the difference between saturated and unsaturated fatty acid?

A

saturated: no double bonds in acyl chains, end in anoic e.g butyric acid
unsaturated: 1 to several double bonds in acyl chain, end in enoic e.g. oleic acid

124
Q

what’s the difference between fat and oil

A

fats have more/all available bonding sites TAKEN UP by Hydrogen (saturated). whereas, oils have fewer hydrogens on the account of double bonds (unsaturated) they are also liquid at room temperature

125
Q

what is a liposome?

A

a minute spherical sac of phospholipid molecules enclosing a water droplet, especially as formed artificially to carry drugs or other substances into the tissues.

126
Q

what is a micelle?

A

ggregate of surfactant phospholipid molecules dispersed in a liquid, forming a colloidal suspension.

127
Q

what is the basic structure of a phospholipid

A

glycerol

phosphate

fatty acid side chain

128
Q

briefly describe the following and their funtion

cytoplasm/cytosol/mitochondria/peroxisomes/nucleus/lysosomes/ER/Golgi

A

cytoplasm → contains all cell organelles except nucleus

cytosol → densely packed aqueous gel, protein synthesis

mitochondria → cellular respiration/apoprosis/oxidative phosphorylation

lysosomes → cellular digestion/enzyme function site

peroxisomes → site of oxygen utilization

nucleus → DNA/RNA synthesis

ER → lipid synthesis/protein distribution

Golgi → modification/sorting/packaging of proteins + delivery and secretion

lysosomes → cellular digestion

129
Q

is oxygen needed to produce ATP

A

Without oxygen, organisms can split glucose into just two molecules of pyruvate. This releases only enough energy to make two ATP molecules. With oxygen, organisms can break down glucose all the way to carbon dioxide. This releases enough energy to produce up to 38 ATP molecules

PH1123 Microbiology (9 decks)

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